Phenolic condensation product and process of making same.



UNITED STATES PATENT OFFICE. 1

LEO H. BAEKELAND, OF YONKERS, AND AUGUST H. GOTTHELF, OF HASTINGS-UPON- HU 'DSON, NEW YORK.

' PHENOLIO CONDENSATION PRODUCT AND PROCESS OF MAKING SAME.

No Drawing.

To all whom it may concern:

Be it known that we, (1) LEO H. BAEKE.

LAND and (2) AUGUST H. GOTTHELF, citi- Zens of the United States, residing at (1) Yonkers and (2) Hastings-upon-Hudson, in the county of Westchester and State of New York, have invented certain'new and useful Improvements in Phenolic Condensation Products and Processes of Making Same, of which the following is a specification.

This invention relates to the production of so-called phenoliccondensation products, the object of the invention being to prepare such products by reaction between a fusible phenolic condensation product, and a body possessing at least one methylene group in combination with another group,

which, after yielding the methylene group to the phenolic body, engenders asubstance possessing a low degree of volatility, combined with non-miscibility with water, low electrical conductivity, and the capacity of serving as a solid solvent in the product.

Heretofore phenolic condensation prod- .ucts, Whether of the fusible and resinous or infusible and insoluble types, have been commonly prepared 'by reaction between phenolic bodies and bodies possessing reactive methylene groups combined with oxygen, as in formaldehyde, its polymers and hydrates; or with nitrogen as in hexamethylentetramin and similar methylene amins; or with halogens as in methylene dichlorid; or with alcoholic groups as inv methylal; or with acid radicles-as in methylene acetate. In case formaldehyde (CH O) or its hydrates, as methylene glycol, its polymers or the hydrates of its polymers, be used, water is formed in the ensuing reaction and may constitute a disturb-' ing factor for certain purposes unless carefully removed; in case of certain methylene amins, such as hexamethylentetramin, ammonia is liberated and may likewise constitute a disturbing factor: in case of halogen compounds, the corresponding halogen acids are formed: in case of methylal, alcohol is set free; and in case of methylene esters such as methylene acetate, the corresponding acids are set free. In all methods heretofore used the production of the phenolic condensation productvhas been accompanied by the formation of another product,

similar reactions and which has Specification of Letters Patent. 7 Patented Feb. 20, 191 '7. Application filed October 17 1913. Serial No. 795,780.

which, by reason of its relative volatility,

tends, at the reacting-temperature, to sepaby the present invention, according to which the group in conjunction with which the methylene is'supplied is of such character that no products of low insulating-value,

or attracting or retaining water or am; 'monia, or soluble in water, or of suflicient volatility to constitute a disturbing factor,

can be formed.

A typical methylene compound suitable for use in conjunction with our invention is the substance which results from the reaction of formaldehyde upon anilinor from been designated as anhydro -formaldehyde :anilin e L CH2)3 Organisclwn Uhemz'e, third edit1on,'vol. 2, page 4-12). We have found that this substance is capable of entering into reaction with many phenolic bodies, yielding compounds which may vary widely in character according'to the nature of the phenolic body chosen, the proportions of the reagents and the-reacting-conditions. For instance, the product of the reaction may be permanently fusible or even liquid, or it may, when subjected to heat, undergo transformation intoa hard, infusible and insoluble mass, or into a substance presenting characteristics intermediate these extremes.

Ordinary phenol or cresol, when caused to react directly with anhydro-formaldehyde-anilin, tends to yield liquid or pasty condensation products which are not ren-.

dered hard by simple heating, either under pressure or otherwise, unless by heating in open vessels for a long time at high tempratures.

Products of a harder and less fusible type are obtained when a portion of the methyl- (Beilstein, Handbuch der I are desired, in two or more stages. An exitmple of such multi-stage process is as folows:

We first prepare, according to any known or suitable method, a phenolic condensation product of the so-called fusible or resinous type, such as have been variously deslgnated in the art as shellac-substitutes, novolak,

I phenol resins, saliretins, saliretin-bodies,

and the like. Such resinous substances, hereinafter for convenience designated simply as fusible phenolic resins, may be prepared for example by such methods as are described in the following patents and publications, to wit British patents to Blumer 12,880 of 1902 and 6823 of 1903; De Laire French Patent 361,539, British 15,517 of 1905, German 189,262; British patent to Wetter (Knoll).

any desired or known manner, is added the" required amount of anhydro-formaldehydeanilin. The two substances may be simply mixed or melted together in proper proportions, and a primary product obtained which is solid, amorphous, resinous, insoluble in water, soluble in acetone, and mixtures ofwood alcohol and acetone, and which is initiallyfusible but becomes infusible and considerably harder upon heating at a sufficiently high temperature, for example at 160 C. This heating may be done at ordinary atmospheric pressure or at pressures higher or lower than atmospheric pre$ure, because this product hardens' withoutengendering disturbing gas or readily volatile substances; although as a rule for'molding purposes and for obtaining a very compact and homogeneous product, an increased pressure is advantageous, because it prevents voids or irregularitiesdue to mechanically interposed air. Such increased pressure may be applied in a heated hydraulic or other press, with simultaneous molding, or in a closed vessel .or chamber, under pressure of a ,gas-or liquid, according to the purpose intended.

In order to obtain a product of highest dielectric properties or of great insulatingvalue, it is desirable or essential that the fusible phenolic resin should be prepared with the necessary care, excluding or removing such impurities as might impair its insulating properties; for instance, it should be freed as far as practicable from water, or too great an excess of phenol, or disturbing condensin -agents, such as are employed in certain o the prior processes above referred to.

If only 1 small proportions of anhydroformaldehyde-anilin are used, the resulting product remains fusible, even after long heating, although it may become decidedly hardened. For instance, if we mix or melt '100 parts by weight of fusible phenolic resin with 20 parts of, anhydro-formaldehydeanilin, we obtain a resinous mass which on further application of heat, becomes harder or less fusible, but remains fusible and soluble, notwithstanding longer heating, and can thus be used as a substitute for shellac or other natural resin, serving for instance for the preparation of certain varnishes, not requiring infusibility.

If, however, the proportion of anhydroformaldehyde-anilin be sufliciently increased, we obtain a primary product which after suflicientlylong application of a sufficiently high temperature, becomes infusible and very hard after cooling, softening some what when again heatedwithout however entering into fusion. In order to obtain such infusible product, we take, for instance, 100 parts by weight of suitably prepared fusible phenolic resin, and add thereto .100 parts of anhydro-formaldehyde-anilin, the mixture being finally heated to a temperature ofv about 160 C. until it is infusible. These proportions may be varied widely, allowing a slow transition and affording a wide range of products from the fusible products formed with relatively low proportions of anhydro-formaldehyde-anilin to the infusible products formed with relatively high proportions of anhydro-formaldehydeanilin with all the advan'tages which this implies for the numerous special industrial applications of a product of this character. According, to the character of the product desired, the proportion of anhydro-formaldehyde-anilin to parts of fusible'phenolic resln, may in ordinary practive vary from 20 to 200 parts, the lower proportions of anhydro-formaldehyde-anilin yielding decidedly fusible final products.

The resistance of the products to the action of such chemicals as alcohol, acetone and dilute caustic soda, increases with the proportion of anhydro-formaldehyde-anilin used. For example, products containing from 150 to 200 parts of anhydro-formaldehyde-anilin to 100 parts of fusible phenolic resin, were not apparently acted upon by 10% caustic soda solutions, or by methyl alcohol, after eleven days at room temperatures, and were only slightly softened by acetone.

The final products prepared as above may .vary in appearance according to the nature The term readily-volatile byproducts is herein employed to designate such-byproducts of reaction as water, ammonia, the halogen acids, alcohol, acetic acid and the like.

In the preparation of industrial products and'compositions consisting of or containing the hereindescribed reaction products, it is tobe understood that We may incorporate such'substances, as for example those of a fibrous or cellular nature, or inert fillers or substances forming solid solutions, as are desirable for partlcular purposes; we may also employ heat and pressure to any required degree for'hardening or molding operations; and, in general, we may apply such manipulations and devlces and pro-. 'vide such additions as are now used in this interior of the voluminous articles made thereof.

Instead of eifectlng a direct reaction be tween the fusible phenolic resin and anhydro formaldehyde a-nilin, as above de-- scribed, we may incorporate anilin with the fusible phenolic resin, together with any body possessing a mobile methylene group and serving to transform the fusible resin into a body of the infusible type, as described in Patent No. 1,038,475 to L. H. Baekeland, the reaction being carried out according to the present invention, in presence of the anilin or its derivates. Similarly, the anhydro-formaldehyde-anilin may be partially replaced by. another body containing a. mobile methylene group, or by mixtures of such bodies with anilin. Typical bodies possessing a mobile methylene group are formaldehyde, paraform, or trioxymethylene, methylene amms, as hexamethylentetramin or the like. For electrical purposes, at least, products thus formed are regarded as less desirable on account of the possibility of the retention in the hardened mass of small proportions of water,

ammonia, or other disturbing bodies.

A further modification of the process consists in incorporating anhydro-formaldehyde-anilin with a phenolic condensation product which is directly transformable by simple heating into an infusible product, that is to say, which is capable of undergoing such transformation without the addition of anhydro-formaldehyde-anilin, or other bodies containing a mobile methylene group. For example, if We mix together equal parts of anhydro-formaldehyde-anilin and an initial phenoliccondensation product which is itself directly transformableby heat into an infusible body, and the mixture be heated under conditions to accomplish such transformation, say at 160 6., it is found that the resulting body is decidedly harder and more resistive than the product resulting from heating such initial condensation product with a similar proportion of anilin; it moreover possesses a decidedly higher insulating-value.

It is self-evident that instead I of using This application is a'continuation in part of our prior application Serial N o. 7 76,847 filed July 1, 1913.

We claim: v

1. The process of preparing phenolic condensation products which consists in heating a fusible phenolic condensation product with a reactive methylene compound, which does not in the reaction, yield a readily-volatile byproduct.

2. The process of preparing phenolic condensation products which consists in heating a fusible phenolic condensation product with a suflicient proportion of a reactive methy1- ene compound, which does not in the reaction yield a readily-volatile byproduct, and thereby producing an infusible final product.

3. The process of preparing phenolic condensation products which consists in heating.

a fusible phenolic condensation product with anhydro-formaldehyde-anilin.

4. The process of preparing phenolic condensation products which consists in heat- .ing a fusible phenolic condensation product r with a suflicient proportion of anhydroformaldehyde-anilin, and thereby producing an infusible final product.

5. The process of preparing phenolic condensation products which consists in heating a fusible phenolic resin with a reactive methylene compound, which does not in the reaction yield a readily-volatile byproduct.

6. The process of preparing phenolic'con densation products which consists in heating a fusible phenolic resin with a sufficient proportion of anhydro-formaldehyde anilin. and thereby producing an infusible final product.

9. The process of preparing phenolic condensation products which consists in heating a fusible phenolic condensation product with anilin and a body containing mobile methylene groups, or reaction products of anilin and such body.

10. The process of preparing phenolic condensation products which consists in heating a fusible phenolic resin with anilin and a body containing mobile methylene groups, or reaction products of anilin and .such body.

11. The process of preparing phenolic -;condens'ation products, which consists in @aQr-eacting upon a fusible phenolic resin with abody containing a reactive methylene 'group, combined with another group which "[aftergyielding the methylene group to the phenolic body engenders a substance characproductpf reaction between a fusible'phenolic resin and anhydro-formaldehyde-anilin, said product characterized by its initial fusibility, and its capability of transformation by heat into a hard, homggeneous, nonporous product without evolution of a readily-volatile byproduct of reaction.

14. As a new compositlon of matter, the

product of reaction between a fusible phe nolic resin and anhydro-formaldehyde-anilin, said product being hard, homogeneous, non-porous, of high insulating-value and free from readily-Volatile byproducts of reaction.

15. As a new composition of matter, the

product of reaction between a fusible phenolic condensation product and anhydroformaldehyde-anilin, said product being hard, homogeneous, non-porous, infusible, of

high insulating-value and freefrom readilyvolatile byproducts of reaction.

I In testimony whereof, we aflix our signatures in presence of two witnesses.

LEO H. BAEKELAND. AUGUST H. eorrnnnr.

Witnesses:

HENRIETTA G. NEWMAN, MARY E. Scnrornrne. 

